Europeans brought tuberculosis to America
The most common form of Mycobacterium tuberculosis (TB) originated in Europe and spread to Asia, Africa and America through European explorers and colonizers, according to a study published by the journal Science Advances, which includes the Efe news agency.
This is the "Most complete genomic analysis to date" of the most widespread form of tuberculosis, lineage 4, and "significantly" increases the understanding of the origin and subsequent spread of this disease, whose global burden has slowly decreased over the last decade, according to the authors.
For the report, researchers from the Norwegian Institute of Public Health analyzed genomic sequences of 1,669 samples of this type of tuberculosis taken at different times in Europe, Africa, Southeast Asia, South America and North America, including ones taken from mummies and other current ones.
Each strain of tuberculosis was placed in a family tree of the family and its location was analyzed geographically over time.
The results showed that lineage 4 emerged in Europe about a thousand years ago, before becoming the globally dominant form of tuberculosis.
The earliest introductions of this type of tuberculosis in Africa occurred in the Republic of the Congo in the fifteenth century, before spreading throughout the continent to South Africa, Uganda and Malawi in the late seventeenth century.
This reflects "faithfully", according to the authors, the European colonial history in Africa south of the Sahara with the first Portuguese forts and trading posts established on the Gold Coast (present-day Ghana) in 1482, followed by European colonial expansion and the African internal migration.
The document also shows that Europeans took tuberculosis to South America relatively soon after the arrival of Europeans to the continent in 1492, with a marked increase of lineage 4 at the end of the 17th century.
The team also mapped the evolution of drug-resistant strains and found that they have barely spread beyond the country in which they originated.
"Our findings suggest that, at least for lineage 4, resistance to antibiotics is a local challenge present in multiple countries and regions, but with minimal spread among them," said Vegard Eldholm of the Norwegian Institute of Public Health.
Therefore, countries that manage to stop the transmission of resistant strains within their territory "should expect a massive decrease in drug-resistant tuberculosis," said Eldholm.
However, the scientist said that these patterns could change in the future, especially if the burden of resistance to antibiotics continues to grow. EFE
